This invention relates to a portable industrial filter system that is portable for connection to a ventline and that has no moving parts. In particular, the invention relates to a filter system that is adapted for connection to the vent port of a receptacle tank receiver to which dry fluid substance, such as hematite, cement, sand or the like, is being conveyed pneumatically.
Conventionally, various kinds of dry fluid substances, including drilling muds known as barite, hematite, cement, blasting grit, sand and other products are moved pneumatically from one receptacle to another. For example, if a barite is to be used in a drilling operation, it is kept stored in dry powder form. For this purpose there is a storage receptacle on site from which the substance can be withdrawn as needed for use, such as in oil-drilling. To replenish the barite in the storage receptacle, a delivery tanker truck having a closed tank brings the powdered substance to the site. The substance is transferred under pneumatic pressure from the vehicle tank to the storage receptacle. This is done by connecting a hose between the vehicle tank and the storage receptacle and operating a blower to pressurize the vehicle tank. The pressurization of air within the tank causes substance to be entrained in the air, and air and substance flow in a stream through the hose to the storage receptacle. In order for this flow to continue, there must be a vent port in the storage receptacle to relieve the pressure.
Desirably, only air will exit through the vent port. However, many of the substances transferred by this conventional method are of powder form, and much of the substance remains with the exhaust air that is discharged through the vent port to the environment. Conventionally, this substance is allowed to discharge directly into the atmosphere, or the vent line is submerged in a body of water, such as a pond or stream, and the substance is discharged into that water. Both of these discharges into the environment are objectionable.
Many efforts have been made to filter these kinds of powder substances, and the most common effort has incorporated a fan dust collector. A fan dust collector is very expensive, both to build and to maintain, and incorporates its own blowing mechanism, and it is stationary so it can be used only at a particular site. Also, when the fan dust collector fills with substance, a problem is created of how to dispose of that collected substance.
Prior art filter systems have incorporated many constructions. These include a cyclone separator for separating relatively heavy particles from a moving stream coupled with a fine filter system for filtering lighter, more powdery particles. However, the overall construction of the filter system of the subject invention, incorporating no moving parts, retaining the feature of portability, being usable to filter dry fluid substance from a moving air stream, and being purgeable to return collected substance to a collecting receiver, has created a significant advantage over the prior art filter systems.